Insulator.



0. MOL. GRAHAM.

INSULATOR. APPLICATION FILED AUG.4, 1908.

930,750. Pat ented Aug. 10, 1909.

CHARLES McIiAOHLAN GRAHAM, OF MALVERN, VICTORIA, AUSTRALIA.

nis'ULA'roR.

Specification of Letters Patent.

rammed Aug. 10, 1909.

application filed August 4, 1908 Serial No. 446,871.

To all whomit may concern: Be it known that 1, CHARLES lllCLACHLAN GRAHAM, a subgect of the lung of (xreat Britain and lrelanr-l, residing at 16 Isabella street, Malvern, ii the county of Bourke; State of Victoria and ommonwcalth of Australia, civil servant have invented a certain new and useful Improved Insulator, of whichthe following is a specification.

This inventioni'elates to insulators com-- posed of such non-conductin material as glass, earthenware or porcelain, to which electric wires or similar bodies are attached.

In the past a variety of such devices have been used, the most common and general of which are those known as the double-shed variety usually manufactured from porce-. lftlll. v i The chief objections to many of these insulators, have been their liability to breakage, their comparatively high conductivity when broken, or when possessing flaws or cracks in the non-conducting material and the leakage .of the ciirrent which takes place (more or less) at the support. ary to cover an insulator withan iron cap when rendered excessively liable to breakage, but it is also recognized that iron capped insulators have increased. ob ioctions and should only be used in extreme cases.

This invention contemplates providing air insulator giving the highest possible resistance to leakage of the current, which is both light and durable, contains the maximum of insulatin effect with aminimum of material,

1 P g has a dripping hp from which all the moisture coming in contact with the insulating medium is precipitated, is easily attached to its support which may be of non-conducting material, is structurally strong and entirely prevents any possible diversion of current from an electrified body attached to it. Further, upsplashing of rain water in wet weather is obviated and foreign substances to a large extent are excluded from the interior of the insulator.

According to this invention the vital parts of the insulator are surrounded by a protcctor preventing injury by. stone throwers or during transportation and thus lowering. the percentage of breakages. This protector is of special character and preferably made of a non-conducting material such as wood. The insulator support may also be of a cheap and effective character and a combination is produced which is most effective in humid It is CllSllOIl'l- 1 the. insulating medium.

or damp climates and the parts of which are easily renewed and inexpensivelymaint ained.

Other advantages possessed will be manifest and further objects apparent from the 66 following dcscriptio Referring to the drawings which form a part of this specification. Figure 1 represents an elevation partlyin section, of the iiisulating medium. Fig. 2 is an elevation partly in section of the protector. Fig. 3 is a sectional viewof the protector inside of which is the insulating medium upon its support. Similar numerals of reference indicate corresponding or like parts where they occur in the several views.

On reference to the drawings it will be seen that the insulating medium has )ICfGl' ably a parallel wall 2, the thickness 0 which will depend upon circumstances. Thesaid insulating medium isformcd of glass, earthenwdraporcelain, or other suitable mate. rials. The said wall 2 has a dripping lip 3 beneath a conical annular cha'mber 4 forming' its bottom. The outside of thesaid wall 2 has an exterior thread 5 thereon (Fig. 1) which may extend from the, top to the bottom thereof or for a portion of that distance. Inside the said wall is an internal thread 6 (Fig. 1) extending fromits top to the conical annular chamber at its bottom. Above the wall is a roof 7, the thickness of which will depend upon conditions. It may beiflat inside and outside as shown, or it may be concaveor convex either inside or outside, or both. The said roof may be integral with;

or attached to the insulating medium. Surrounding'the insulating medium s a protector. J This can be made of any material or combination of materials, and need not beef a non conducting nature. It has an upper wall 8 preferably parallel on the inside and the outside. On the outside of the said wall is a wire groove 9 in which, is secured the electrified body to be su ported. Inside the said wall is an interna thread 10 (Fig. 2) registering With the external thread 5 upon Above thetop of the upper wall 8 is a cover 1] whicdmay be ntegral therewith or attached thereto. This coveris preferably convex upon its top. Below the upper wall 8 is a lower wall 12.

The said lower wall 12 is referably thinner than the upper wall 8 withwhich it is intee gral. It extends below the dripping lip 3 and forms a chamber 13 within which and the conical annularchainber 4 above it moisture condenses. The said insulating medium is threaded by its internal thread 6 to the upper endl l of a wooden or like non-conducting support accommodating a metallic or other central reinforcing member 16 having a head 17 and provided on its threaded lower end with a nut 18. In the top of the said non-conducting support is a recess 19 within and below the upper edge of which the head 17 of the central member reposes. The bottom of the non-conducting support rests upon the body 20 to which the insulator is retained by the nut 18 upon the lower end of the central reinforcing-member passing therethrough.

Attached to. or integral with the support is an upsplash preventer 21 which is below.

the insulator or mayflbe within the chamber 1 threaded-around the threaded top of said support. The said insulating medium is screwed down so that-its roof rests upon the top of the said support. The protector 18 then threaded over the external thread 5 of the insulating medium. It in turn is threaded downwardly until its cover'makes contact with the roof of the said insulating medium. ,The insulator is then attached to any desired body by the central member 16.

I As the controlling features of this invention could be otherwise applied and carried out by various modifications, and arrangements, without (1e arting from its spirit and scope, it is inten ed and desired that the matter contained in' the foregoing description shall be interpreted as illustrative of an The internal embodiment at present preferred and not in a limitlng sense. 1'

Having now. described my invention, what I claim as new and desire to secure by Letters Patent is r V 1. The herein described insulator comprising a central bolt or reinforcing member,

a wooden support transfixed by said bolt and provided with a threaded upper end; an nverted cup -'shape,d insulating medium threaded both internally and externally and screwed upon the upper endof said supportand having an annular chamber in its lower end and a dripping lip at the outer edge of said chamber, and an inverted cup-shaped protector internally threaded and screwed upon said insulating medium and depending .below the dripping lip on said medium but separated from the lip by an annular chamber, and means toprevent water "splashing into said chamber, substantially as described. r

2. The herein described insulator comprising a central bolt or reinforcing member, a wooden support surrounding said member and provided with a circumferential upsplash preventer and having athreaded up- 'p'er end; an inverted cup-shaped insulating medium threaded internally and externally and screwed upon the upper end of said support and having an annular chamber on its edge of said .chamber','. th'e said lip lying above the plane of the upsplash preventer; and an inverted cup-shaped protector inter- I nally threaded and screwed upon the insuower end and a dripping'lip at'the outer lating medium and depending below the dripping lip on said medium but separated from the same and from the upsplash preventer by an annular chamber, said chamber being substantially closed-by said upsplash preventer.

In testlmony whereof I affix mysignature in the presence of two subscribing witnesses.

CHARLES MQLAQHIFANG'RAHAM. Witnesses CECIL 'W. LE PLAsTnmR,

GEORGE A. URnn. 

